Undo unwanted change to SkTypes.h.

This was undone in an editor, but didn't get commited.

Change-Id: Id410de0a066b3fe65119d0b72c6f29a1f91d1ebb
Reviewed-on: https://skia-review.googlesource.com/39700
Reviewed-by: Ben Wagner <bungeman@google.com>
Commit-Queue: Ben Wagner <bungeman@google.com>
diff --git a/include/core/SkTypes.h b/include/core/SkTypes.h
index 9887c91..b453249 100644
--- a/include/core/SkTypes.h
+++ b/include/core/SkTypes.h
@@ -216,7 +216,7 @@
 
 /** Returns 0 or 1 based on the condition
 */
-#define SkToBool(cond)  (bool(cond))
+#define SkToBool(cond)  ((cond) != 0)
 
 #define SK_MaxS16   32767
 #define SK_MinS16   -32767